The present invention relates in general to fiber optic cable or ribbon connectors, and more particularly, the present invention relates to a guide boot for fiber optic cables that allows a fiber optic cable to be bent, twisted or rotated without damaging the optical fiber in the cable or affecting signal quality.
Optical fibers are used in a variety of applications ranging from large scale telephonic communication systems to laser surgery, and generally include a transparent core made, for example, of glass surrounded by cladding which is also made of transparent material but has a different index of refraction than the core. The core and cladding are enclosed by a protective flexible jacket. Connectors are used to join fibers to each other and to active or passive optical components such as sources, detectors, repeaters, switches, and attenuators.
As is well known in fiber optics, bending or twisting fiber optic cable too sharply can lead to a reduction in the signal transmission quality of the cable. However, it is necessary to be able to bend fiber optic cables in order to route the cables within, to and from equipment such as computers, connector panels, junctions boxes, etc. Accordingly, fiber optic cables are evaluated to determine a minimum bend radius. As long as a fiber optic cable is bent at a radius that is equal to or greater than the minimum bend radius, there should be no reduction in the transmission quality of the cable. However, if a fiber optic cable is bent at a radius below the minimum bend radius determined for such cable, there is a potential for a reduction in signal transmission quality through the bend.
The process of terminating the fiber optic cable in a connector is commonly referred to as xe2x80x9cconnectorization.xe2x80x9d The point at which a fiber optic cable extends into a connector joined on the end of the cable is an especially susceptible point of the cable bending below the minimum bend radius of the cable. To prevent such unacceptable bending, it is well known to install reinforcing boots during connectorization that extend out from the connector and encase a length of the cable extending from the connector. Such boots are permanently installed during connectorization. These boots provide enough reinforcement to limit the bend radius of the cable at the cable/connector junction.
However, there are problems in relying merely on reinforcing boots to prevent excessive bending of the fiber optic cable. For example, hundreds of fiber optic cables are commonly routed through and connected in connector panels or junction boxes with limited space. The connectors of such fiber optic cables are commonly inserted into horizontally oriented connectors that are arranged in a vertical panel in the junction box. The cables are routed in a direction perpendicular to their connector. The door of such junction boxes is also vertical and typically closes in a plane parallel to the panel of connectors. The space between the closed door and the panel of connectors is desired to be as small as possible; however, if the space is too small, the door will excessively bend the boot encased portion of the cable when it is closed.
Right angle boots are typically more rigid than the typical straight boot.
Thus, a need exists for a guide boot that can receive a fiber optic cable or ribbon and circumferentially rotate or twist the cable and insure that the cable will not be excessively bent. Additionally, such a guide needs to be removably installable.
The present invention is directed to a single-piece guide boot for a fiber optic ribbon cable. The guide boot comprises an outer sleeve or body that defines an inner passageway, and at one end has a termination plug with termination port for receiving the cable. The inner passageway is dimensioned to allow a user to insert a cable through the passageway. The body with the inner passageway is used for guiding the cable while also allowing the cable to bend and to twist. The body is angled at the desired angle (ensuring a satisfactory radius of curvature), such as about 45 degrees or about 90 degrees. The body could have an outer diameter that decreases toward the first end. The inner passageway could be round in cross-section and tapered along its length. Preferably, the cable is inserted into and through the guide boot with twisting or rotation, with the cable thereafter prevented from further twisting or rotation in the guide boot.
The foregoing and other aspects of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.